4.3
MEDIUM CVSS 3.1
CVE-2026-55566
Yamcs: DOM XSS in Extension Routing
Description

Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs processes attacker-controlled data from the /ext URL route in yamcs-web/src/main/webapp/projects/webapp/src/app/core/routes/extension.matcher.ts, extension.component.ts, and app.component.ts without checking registered plugin IDs before DOM rendering through innerHTML. A crafted URL can execute JavaScript when opened by a user. The script can read data available to the Yamcs web application and perform actions in the user context. This issue is fixed in versions 5.12.8 and 5.13.2.

INFO

Published Date :

Aug. 28, 2026, 8:18 p.m.

Last Modified :

Aug. 28, 2026, 10:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55566 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Spaceapplications yamcs
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM [email protected]
CVSS 3.1 MEDIUM MITRE-CVE
Solution
Update Yamcs to a fixed version to prevent JavaScript execution from crafted URLs.
  • Update Yamcs to version 5.12.8 or later.
  • Update Yamcs to version 5.13.2 or later.
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55566 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-55566 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55566 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55566 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/yamcs/yamcs/security/advisories/GHSA-9272-wg2r-7xmx
    Added SSVC {'id': 'CVE-2026-55566', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-08-28T20:30:29.994741Z'}
  • New CVE Received by [email protected]

    Aug. 28, 2026

    Action Type Old Value New Value
    Added Description Yamcs is a mission control framework. Prior to 5.12.8 and 5.13.2, Yamcs processes attacker-controlled data from the /ext URL route in yamcs-web/src/main/webapp/projects/webapp/src/app/core/routes/extension.matcher.ts, extension.component.ts, and app.component.ts without checking registered plugin IDs before DOM rendering through innerHTML. A crafted URL can execute JavaScript when opened by a user. The script can read data available to the Yamcs web application and perform actions in the user context. This issue is fixed in versions 5.12.8 and 5.13.2.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
    Added CWE CWE-79
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/55xxx/CVE-2026-55566.json">CVE-2026-55566</a>
    Added Reference https://github.com/yamcs/yamcs/commit/8e18e279d8ce761c21f4f67bbd06a1bff804d297
    Added Reference https://github.com/yamcs/yamcs/commit/ecf34a4e2ccbe085e6ceff0253595b24d5ecb4aa
    Added Reference https://github.com/yamcs/yamcs/releases/tag/yamcs-5.12.8
    Added Reference https://github.com/yamcs/yamcs/releases/tag/yamcs-5.13.2
    Added Reference https://github.com/yamcs/yamcs/security/advisories/GHSA-9272-wg2r-7xmx
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.